Lock core puller for spring retained locks

ABSTRACT

A device for removing a spring retained lock core from a lock without damage thereto comprising a threaded shaft having at one end a bit to be inserted in the keyway past a couple of lock pins, and a threaded crank on the other end adapted to bear on a pressure plate to withdraw the bit, lock mechanism and lock core from the lock.

[111 3,816,899 June 18, 1974 United States Patent [191 Kitts 9/1959 Mikeska................ FOREIGN PATENTS OR APPLICATIONS 15,450 0/1900 Great Britain....i................... 29/263 1,078,241 29/264 George J. Kitts, 38 Queenlily, Levittown, Pa. 19057 Primary Examiner-A1 Lawrence Smith ssistant Examiner-Roscoe V. Parker A device for removin from a lock without P MD. FA .1] 2 22 [.1

52 us. 29/263, 81/3 R ABSTRACT [51] Int. 323p 19/04 g a spring retained lock core [58] Field of Search 81/3 R; 29/234, 256, 258, damage h re o omprising a 29/263, 264 threaded shaft having at one end a bit to be inserted in the keyway past a c lock pins, and a threaded ouple of ma mm d r m 3 m 0.5 S n 6 a r 1" u b .W e F m t g dk .m .wm w a n m 3 5 m m. wam mmmc d e m hunt w n m ow m m e mmm CD-C m w Q2 9. 2" W m W: wAMW t .IPHH Mm we m p mm GAHM FTBC mSZS D U99 NHH U45 23 I0 .1 w 6 3, 5 mm LOCK CORE PULLER FOR SPRING RETAINED LOCKS SPECIFICATION This invention relates generally to means for pulling the cores of locks and more particularly to a simple but effective device for removing the spring retained cylinder and core of cylinder and the cores of other locks without damage thereto.

Various means are known in the art for forcing locks to gain entry to rooms, cabinets, automobiles, etc. and

these are objectionable in that they require the services of a locksmith, result in damage to the lock or a component thereof, or are as unavailable as the key to the lock.

Accordingly, the main object of the present invention is to provide a simple, effective device for pulling the spring retained cylinders and cores of cylinder locks and cores of other locks without damage thereto.

An important object of the present invention is to provide a device of the type described wherein its core pulling tip is readily interchangeable so as to pull the spring retained cores of various types of cylinder locks.

Another important object of the present invention is to provide an improved device for removing the spring retained cores of various types of locks which can be readily detached from the lock core after its removal from its cylinder.

Other objects and advantages of the present invention will become apparent during the course of the following description.

In the drawings, I have shown one embodiment of the invention. In this showing:

FIG. 1 is a perspective view of the core-pulling device showing its core pulling tip about to enter the keyway of the core of a cylinder lock of the door knob of a closure;

FIG. 2 is an elevational view of the outer end of the core-pulling device comprising the present invention;

FIG. 3 is a fragmentary perspective view of the threaded shaft detachably mounting one of several types of bits for pulling the spring retained cores of cyl inder locks;

FIG. 4 is a central, vertical, longitudinal sectional view of the invention in operative position with its bit behind a pair of cylinder core pins and ready to pull the core and cylinder from the knob; and

FIG. 5 is a similar view of a pick employed to raise the pins of a core to effect removal of the bit of the core puller from the core after its removal.

Referring to the drawings, numeral designates the lock core puller as a whole which comprises a rectangular threaded shaft 12 having a slot 14 for the detachable reception of one of several types of bits 16 as by pins 18, a pressure plate 20, and a threaded wing nut 22 on the outer end of shaft 12.

The portion of the pressure plate 20 shown which may be of any desired shape, is preferably semi-circular to enable the operator to see the bit 16 as he guides it to a keyway and is provided with a threaded boltreceiving aperture 21 of larger diameter than the shaft 12. The pressure plate portion 20 is fixed to the outer end of an open ended cylinder 24 which is the pressure plate proper, and is of a diameter sufficiently great to fit against the face 28 of a lock or door knob 26 having a cylinder lock or over it to bear against the face of a door, etc. 29 to afford the bearing for the pressure plate 20. Where a closure 29 is provided with an L-handle or T-handle as is the case on many storage cabinets, a steady bearing for the cylinder 24 is attained by a pair of adjustable legs 30 which are mounted on opposite sides of the cylinder 24 by means of spaced knurled head screws 32 projecting through the slot 34 in the legs 30. The legs are readily slid to the bearing face of a lock or closure when the cylinder 24 is placed against the L or T-shaped closure handle (not shown), by means of outturned leg flanges 36. The cylindrical cylinder 24 is provided with opposed open slots 25 on each side to accommodate the elongated ears of certain locks.

As stated, the device comprising the present invention is suitable for use with locks having spring retained cores of which there are a number of effective and popular makes. As shown in the drawings, a cylinder lock 27 having an outer face 28 may be mounted in a knob 26 of a closure 29 or in the L or T-shaped handles thereof. Conventionally, a cylinder lock 27 of the pin tumbler mechanism type is provided with a tightly fitting core 40 having a keyway 42 into which a plurality of tumbler pins 44 are projected by springs 46. Each pin has one or two parts so that when the proper key is inserted into the keyway 42, each pin is at the proper elevation within the core to enable the latter to turn freely and rotate the main body lock shank to withdraw a latch. The core 40 and the cylinder lock 27 are at tached to the end of the lock shank (not shown) by a strong horse-shoe shaped spring 48.

In use, when the device 10 comprising the present invention is utilized to withdraw a spring-retained core 40 and its lock cylinder 27, the inner end of the open cylindrical bearing plate 24 is positioned against the outer surface 28 of the lock cylinder or door knob 26 (FIGS. 1 and 4) or over the knob and against the surface 29 of a closure. During this positioning, the tip or bit 16 is visually guided from the outer end of the cylinder 24 so as to enter the keyway 42 until a minimum of 2 pins 44 are passed. The wing nut 22 is now tightened against the bearing plate end portion 20 and the direct line pull of the shaft and tip overcome the tensions of the horseshoe shaped spring 48 and withdraws the core 40 and the lock cylinder 27 from the knob 26. A pair of pliers may now be used to turn the lock shank. To remove the bit 16 from the core, a locksmiths metal pick 54 is employed to raise the pins 44 to permit withdrawal.

It is to be understood that the form of my invention herewith shown and described is to be taken as a preferred example of the same and that various changes in the shape, size and arrangement of parts may be resorted to without departure from the spirit of the invention or the scope of the subjoined claims.

What is claimed is:

1. A device for removing a spring retained core from a lock comprising an open-ended bearing cylinder having one end adapted to bear against the surface of a lock; a pressure plate having an aperture therein fixed to and partially closing the other end of said cylinder to form a viewing opening; a square threaded shaft ex tending through said aperture in alignment with the keyway of the core; an elongated tip terminating in an upwardly extending flange including a rearwardly facing shoulder detachably mounted to one end of said shaft for insertion into the keyway to engage behind a lock pin; and a nut mounted on the other end of said threaded shaft and engageable with said pressure plate to withdraw the core from the lock upon rotation of said nut.

2. A device for removing a spring retained core from a lock comprising, in combination, an open-ended bearing cylinder having one end adapted to be placed over closure knobs and handles and against bearing surfaces containing lock cores; a pressure plate having an aperture therein fixed to and partially closing the other end of said cylinder to form a viewing opening; a square threaded shaft of smaller diameter than said aperture extending therethrough in alignment with the keyway of the core; an elongated tip terminating in an upwardly extending flange including a rearwardly facing shoulder detachably mounted on the inner end thereof for insertion into the keyway to engage behind a tumbler pin of the core; and a nut threadedly mounted on said threaded shaft and engageable upon rotation with the outer surface of said pressure plate to overcome the tension of the spring and withdraw the core of said lock therefrom.

3. The combination recited in claim 1; and a leg mounted on said bearing cylinder as a supplement thereto.

4. The combination recited in claim 3 wherein said leg is adjustable to adapt said bearing cylinder to various bearing surfaces.

5. The combination recited in claim 2; and a leg mounted on said bearing cylinder for steadying it against closure and lock surfaces.

6. The combination recited in claim 5 wherein said leg is adjustable. 

1. A device for removing a spring retained core from a lock comprising an open-ended bearing cylinder having one end adapted to bear against the surface of a lock; a pressure plate having an aperture therein fixed to and partially closing the other end of said cylinder to form a viewing opening; a square threaded shaft extending through said aperture in alignment with the keyway of the core; an elongated tip terminating in an upwardly extending flange including a rearwardly facing shoulder detachably mounted to one end of said shaft for insertion into the keyway to engage behind a lock pin; and a nut mounted on the other end of said threaded shaft and engageable with said pressure plate to withdraw the core from the lock upon rotation of said nut.
 2. A device for removing a spring retained core from a lock comprising, in combination, an open-ended bearing cylinder having one end adapted to be placed over closure knobs and handles and against bearing surfaces containing lock cores; a pressure plate having an aperture therein fixed to and partially closing the other end of said cylinder to form a viewing opening; a square threaded shaft of smallEr diameter than said aperture extending therethrough in alignment with the keyway of the core; an elongated tip terminating in an upwardly extending flange including a rearwardly facing shoulder detachably mounted on the inner end thereof for insertion into the keyway to engage behind a tumbler pin of the core; and a nut threadedly mounted on said threaded shaft and engageable upon rotation with the outer surface of said pressure plate to overcome the tension of the spring and withdraw the core of said lock therefrom.
 3. The combination recited in claim 1; and a leg mounted on said bearing cylinder as a supplement thereto.
 4. The combination recited in claim 3 wherein said leg is adjustable to adapt said bearing cylinder to various bearing surfaces.
 5. The combination recited in claim 2; and a leg mounted on said bearing cylinder for steadying it against closure and lock surfaces.
 6. The combination recited in claim 5 wherein said leg is adjustable. 